Introduction

There is a compelling logic about the standard route to the Lorentz transformations and relativistic dynamics, which can be summarised as follows.

• Bradley's observations of stellar aberration of 1727–8 imply that the Earth moves through a stationary aether.

• The null result of the Michelson–Morley experiment of 1887 indicates that there is no detectable motion of the Earth through the aether.

• Einstein's second postulate of special relativity states that the speed of light is the same for an observer in any inertial frame of reference.

• Derivation of the Lorentz transformations and relativistic kinematics follows.

• The invariance of all the laws of physics under Lorentz transformation is invoked, according to Einstein's first postulate of relativity.

• Relativistic dynamics can now be derived.

• A consequence of the latter is E = mc2.

• The invariance of Maxwell's equations follows automatically from the properties of the Lorentz transformations.

It is a splendid story, but is not at all how the theory came about historically. As with many of the most dramatic turning points in the history of physics, the route to the final theory was tortuous and involved many blind alleys. The origins of special relativity have been the subject of a great deal of study by historians of science and, fortunately, there are two excellent and accessible surveys of the key events by Stachel.